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  <title>Document</title>
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    var score = Number(prompt("请输入您的分数"))
    if (score > 100 || score < 0) { alert("您输入的分数超过范围") }
    else if (score > 90) { alert("优秀") }
    else if (score > 80) { alert("良好") }
    else if (score >= 60) { alert("及格") }
    else { alert("不及格") }

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